The surprisingly common sleep condition causing drivers to fall asleep at the wheel
Have you ever had to pull over because you felt so tired? Driving while sleepy can be fatal. When you’re exhausted, your reaction times are slower, your concentration levels dip, and your judgement and vision alters.
Most people understand why they feel tired; they had a late night, or they got up extra early to make it to work on time. But many others experience excessive sleepiness during the day without knowing why – and the potential reason for this can be serious. Obstructive sleep apnoea (OSA) is a sleep condition where sufferers stop breathing properly during the night. One of the most common symptoms of OSA is feeling fatigued during the daytime, and this results in many drivers falling asleep at the wheel.
It’s estimated that around 1.5 million adults in the UK have OSA, and that up to 85% of cases are undiagnosed . Aside from excessive daytime sleepiness, snoring is the most frequent symptom of OSA. Snoring occurs when your airway narrows too much during sleep, and the air you breathe is then pulled through it faster. This causes the soft tissue in the back of your throat to dehydrate and vibrate, creating the snoring sound. But in some cases, the airway becomes so narrow that the walls of the airway stick together and close up. This usually happens for 10-30 seconds, but can occur for longer – sometimes up to 50 times an hour or even more. When the airway finally opens up again, the person sleeping will produce a loud, violent snore. This closure event is known as an apnoea, and a partial closure is called a hypopnoea.
Throughout the night, the sufferer’s body will constantly ‘wake itself up’ to a lighter stage of sleep in order to breathe. This is what makes the condition so dangerous for drivers – they’ll be left feeling overly tired the next day, and unable to focus fully on the road.
Night-time symptoms of OSA include:
- Dry mouth
- Frequent awakening
Daytime symptoms include:
- Weight gain
- Short temper
- Poor concentration
- Low mood
It’s a good idea to make an appointment with your doctor if you suspect you have OSA. If you’re subsequently diagnosed with OSA, and feel excessively sleepy when you drive, you should inform the Driver and Vehicle Licensing Agency (DVLA) as soon as possible. The DVLA will begin an enquiry into your condition, and assess whether you’re safe to drive.
In the meantime, you should speak to your doctor about suitable OSA treatments. Once the DVLA recognises that you’re being successfully treated for the condition, you’ll be able to drive safely again. There are several treatment options for OSA; a CPAP machine is most commonly used in severe cases, and uses air pressure to force air through the breathing obstruction. This is done by wearing a mask over the face during sleep. For those with mild-to-moderate OSA, another treatment option is an oral device. Similar to a sports mouthguard, oral devices treat OSA by holding the jaw slightly forward while you sleep. This opens the airway and helps you breathe.
If you’re experiencing any symptoms of OSA, it’s important that you visit your doctor as soon as you can. Ignoring the condition not only puts your life at risk, but the lives of other drivers, passengers and pedestrians.
1. British Lung Foundation (2015), Obstructive sleep apnoea (OSA): Toolkit for commissioning and planning local NHS services in the UK